Opening Modes in Standard I/O

File Mode

Meaning of Mode During Inexistence of file
r Open for reading. If the file does not exist, fopen() returns NULL.
rb Open for reading in binary mode. If the file does not exist, fopen() returns NULL.
w Open for writing. If the file exists, its contents are overwritten. If the file does not exist, it will be created.
wb Open for writing in binary mode. If the file exists, its contents are overwritten. If the file does not exist, it will be created.
a Open for append. i.e, Data is added to end of file. If the file does not exists, it will be created.
ab Open for append in binary mode. i.e, Data is added to end of file. If the file does not exists, it will be created.
r+ Open for both reading and writing. If the file does not exist, fopen() returns NULL.
rb+ Open for both reading and writing in binary mode. If the file does not exist, fopen() returns NULL.
w+ Open for both reading and writing. If the file exists, its contents are overwritten. If the file does not exist, it will be created.
wb+ Open for both reading and writing in binary mode. If the file exists, its contents are overwritten. If the file does not exist, it will be created.
a+ Open for both reading and appending. If the file does not exists, it will be created.
ab+ Open for both reading and appending in binary mode. If the file does not exists, it will be created.

Comments

Post a Comment

Popular posts from this blog

IP Addresses And Subnet Masks

Image
Addressing for intranets (and the Internet) explained TCP/IP is the networking protocol of the Internet, and by extension of intranets. For TCP/IP to work, your network interfaces need to be assigned IP addresses. Note that we said network interfaces and not computers. The IP addresses are assigned to interfaces and not to computers. So, one computer can have more than one IP address. For example, if you have two network cards on your computer, then each of them can have a different IP address either static or dynamic (more about that in a minute). Similarly, if you have a proxy server running, then the machine on which it is installed should have a static IP address. Now, the same machine has to establish a dial-up link to the Internet through, say VSNL. Then the dial-up adapter would be assigned a different dynamic address. What's an IP address? An IP address is a number that represents a device like a network card uniquely on the Internet or on your company's int...
Read more

Simplex communication

Simplex communication is a communication channel that sends information in one direction only. The International Telecommunication Union definition is a communications channel that operates in one direction at a time, but that may be reversible; this is termed half duplex in other contexts
Read more

what is a printer?

Image
A printer is a device that accepts text and graphic output from a computer and transfers the information to paper, usually to standard size sheets of paper. Printers vary in size, speed, sophistication, and cost. In general, more expensive printers are used for higher-resolution color printing. Features of impact Printer The general features of impact printer are- They create the characters by striking  the paper. They print on most types of paper. Multiple (carbon) copies may be printed at once Disadvantages of impact printers They are relatively slow They do not print transparencies (documents printed on clear plastic film for use with over head projector. Dox –matrix are impact printer that draw a character from a series of dots. They are suitable for draft copies and home use, where the quality of finished document is not critical. They are also use for preparing of bills and invoices in hospital because they are cheap and durable. Other printer- las...
Read more